The Aarhus Ø former container port is the site of the new reef-to-be, Source: Aarhus Municipality

Aarhus builds a rock reef to boost marine biodiversity

Aarhus builds a rock reef to boost marine biodiversity

Utilizing leftover materials from a construction project

The coastal Danish city of Aarhus is in the process of building an artificial reef with the purpose of enriching the local marine biodiversity in the bay bearing the same name. The site of the project is Aarhus Ø, the former abandoned container port whose land-adjacent area was developed into the Aarhus Docklands neighbourhood.

What’s more, the rock material needed to create the reef will come from an on-land construction nearby, namely the creation of a 12-kilometre ring road. 2000 tonnes of rock will be placed in the water as a future habitat on Aarhus Island for, among other things, mussels, sea anemones and sea algae.

Maximizing resource utilization

The first stones have already been laid in the water, and within days the reef is expected to be ready for the first animals and plants to move in. Most of the rocks are placed in piles to create cavities between them. Here crustaceans, snails, brush worms and many other animals can hide from fish and crabs. Other stones are laid individually and dispersed on the seabed.

Rune Kilden, an urban developer from the adjacent Lighthouse neighbourhood complex explained his involvement: “After being a deserted container port for many years, Aarhus Ø has today become a vibrant district, where the sea plays a major role and is a natural part of everyday life.

Both residents and visitors to Aarhus Ø swim, kayak, walk along the water. They enjoy the view of the bay and the experiences that life above and below the surface provides. We want to help bring that life and those experiences even closer to the people of Aarhus, so we are happy that we can contribute to this project.”

The material that makes up the new reef comes from another large project in Aarhus - the construction of the upcoming Giber Ringroad, south of Aarhus. Here the large stones forming the reef base originate, having been dug out in the process of the road construction.

The reef is located beside the seaway next to the Lighthouse neighbourhood on Pier 4.



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